import pygame
import sys

pygame.init()
size = width,height = 640, 480
bg=(0,0,0)

clock = pygame.time.Clock()
screen = pygame.display.set_mode(size)
pygame.display.set_caption('Demo')

turtle = pygame.image.load('turtle.png').convert_alpha()
background = pygame.image.load('background.jpg').convert()
position = turtle.get_rect()
position.center = width//2 , height//2

print(position)
print(position[0],position[1])
def blit_alpha(target, source, location, opacity):
    x = location[0]
    y = location[1]
    temp = pygame.Surface((source.get_width(), source.get_height())).convert()

    temp.blit(target, (-x, -y ))
    #temp.blit(source, (0, 0))
    temp.set_alpha(opacity)        
    target.blit(temp, location)
    
while True:
    
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()

    screen.blit(background, (0, 0))
    blit_alpha(screen, turtle, position, 200)
     
    
    pygame.display.flip()
    
    clock.tick(30)
